If someone goes straight to the doctor and gives the symptoms of whiplash, then it is very hard to disprove. Yes insurance companies have made progress, but only against multiple claims from one person or against people who have not sought medical advice.
Someone goes into the back of you and you get yourself to the doctors, get a sick note for whiplash and then wait for the no win no claim brigade to call and get yourself a couple of grand for whiplash injuries. That's the reality of today's society. I hit someone's wall twenty odd years ago...